The invention relates to an apparatus for spraying chemicals, and, more particularly, to a herbicide spraying unit adapted for towable attachment to a tractor to facilitate drift free spraying.
It is generally the practice when spraying chemicals such as herbicides and insecticides to eject the chemical in a fine mist upon the foliage being treated. Oftentimes however, winds cause the mist to drift away from the subject foliage before same is contacted. This creates two problems. First, the purpose of the spraying is frustrated in that the subject foliage is not treated. Secondly, the drift of the spray often contacts areas which are detrimentally affected by the spray. This twofold problem has been addressed by certain prior art spraying devices which have provided "focusing" spray nozzles which intensify the spray stream to reduce drift contamination. However, such devices generally alter the mist characteristics of the chemical and reduce the treatment effectiveness thereof.
Other prior art approaches to reducing spray contamination caused by drift have included spray bars designed for use very close to the sprayed surface whereby the spray pressure can be substantially reduced. Such an effect reduces mist drift but also reduces the rate at which the chemical can be applied as well as the mist characteristics. Furthermore, nozzle modifications for controlling mist drift are generally inconsistent with optimal spraying configurations from a technical standpoint.
It would be an advantage therefore to provide spraying apparatus which could incorporate optimal spray nozzle configurations in an assembly providing confined spray application and the elimination of drift contamination. The invention of the present system is constructed for just such a purpose. The spray bar is enclosed in an elongated housing adapted for ambulatory surface engagement. The housing includes flexibly mounted fore and aft walls for conforming to uneven surfaces over which the housing is permitted to glide. The spray from the spray bar is confined therein during all wind conditions.